The Bortle scale is a nine-level numeric scale that measures the night sky’s brightness of a particular location. It quantifies the astronomical observability of celestial objects and the interference caused by light pollution. John E. Bortle created the scale and published it in the February 2001 edition of Sky & Telescope magazine to help amateur astronomers evaluate the darkness of an observing site, and secondarily, to compare the darkness of observing sites. The scale ranges from Class 1, the darkest skies available on Earth, through Class 9, inner-city skies.
The Milky Way glitters above Yellowstone National Park. David Lane created this stunning multi-image panorama of the night sky over the park’s Pelican Creek – a place that offers great views of Yellowstone Lake. Photo courtesy of David Lane.
The Aoraki Mackenzie International Dark Sky Reserve in New Zealand has a new sign to greet visitors! You can also see the Large Magellanic Cloud, a galaxy visible to the naked eye in the southern hemisphere.
Joshua Tree National Park’s iconic Joshua Trees come in many shapes and sizes. No two are the same. This one is trying to imitate the Milky Way.
Explore Joshua Tree’s unique landscape and photograph the park’s dark skies this Saturday (May 23). An all-night Instameet will give skilled and amateur photographers the chance to capture amazing pics of Joshua Tree’s starry nights. The meetup starts at 8 pm at the park’s Cap Rock. Photo courtesy of Juan Moreno.
Until recently, for all of human history, our ancestors experienced a sky brimming with stars – a night sky that inspired science, religion, philosophy, literature and art. Unfortunately, we’ll never know the great art we’ve lost to light pollution.
Enjoy these beautiful pieces of art inspired by starry night skies and learn how you can help inspire future generation to invent, create and dream.